JP7481422B2 - Control device and control method for loading machine - Google Patents

Description

The present invention relates to a control device and control method for a loading machine.

Patent Document 1 discloses technology related to automatic loading control of a loading machine. Automatic loading control is a control in which a control device receives a loading point designation from an operator of the loading machine, etc., and controls the operation of the loading machine and the work machine to move the bucket to the loading point. According to the technology described in Patent Document 1, the control device stores a time series of the positions of the work machine in advance and operates the work machine according to the time series.

Japanese Patent Application Laid-Open No. 09-256407

According to the technology described in Patent Document 1, the working machine automatically moves to a loading point stored in advance, and unloads soil at the loading point. However, there is a demand for shortening the cycle time in automatic loading.
An object of the present invention is to provide a control device and a control method for a loading machine that can shorten the cycle time in automatic loading control.

According to a first aspect of the present invention, the control device for a loading machine is a control device for a loading machine including a rotating body that rotates around a rotation center and a working machine having a bucket and attached to the rotating body, and includes an operation signal input unit that receives a loading instruction signal from an operator, and an operation signal output unit that outputs an operation signal for the working machine and the rotating body to move the bucket to a loading position above a loading target when the loading instruction signal is received, and outputs an earth discharge operation signal to discharge earth into the bucket when the rotating body faces a soil discharge start orientation that is on the front side of the rotation direction from an end point orientation, which is the orientation in which the rotating body faces when the working machine is located at the loading position.

According to the above aspect, the loading machine control device can shorten the cycle time in automatic loading control.

1 is a schematic diagram showing a configuration of a loading machine according to a first embodiment. FIG. FIG. 2 is a schematic block diagram showing a configuration of a control device according to the first embodiment. FIG. 4 is a diagram illustrating an example of a bucket path according to the first embodiment. 3 is a flowchart showing an automatic loading control method according to the first embodiment. 3 is a flowchart showing an automatic loading control method according to the first embodiment.

Hereinafter, the embodiments will be described in detail with reference to the drawings.
First Embodiment
<Loading machine configuration>
FIG. 1 is a schematic diagram showing the configuration of a loading machine according to a first embodiment.
The loading machine 100 is a work machine that loads earth and sand onto a loading point such as a transport vehicle. The loading machine 100 according to the first embodiment is a hydraulic excavator. Note that the loading machine 100 according to other embodiments may be a loading machine other than a hydraulic excavator. Although the loading machine 100 shown in FIG. 1 is a backhoe excavator, it may also be a face shovel or a rope shovel.
The loading machine 100 includes a traveling body 110, a rotating body 120 supported by the traveling body 110, and a working machine 130 that is hydraulically operated and supported by the rotating body 120. The rotating body 120 is supported so as to be freely rotatable about a rotation center.

The work machine 130 includes a boom 131, an arm 132, a bucket 133, a boom cylinder 134, an arm cylinder 135, a bucket cylinder 136, a boom angle sensor 138, an arm angle sensor 139, and a bucket angle sensor 140.

The base end of the boom 131 is attached to the rotating body 120 via a pin.
The arm 132 connects the boom 131 and the bucket 133. The base end of the arm 132 is attached to the tip of the boom 131 via a pin.
The bucket 133 includes a blade for digging up soil and sand, and a container for transporting the excavated soil. A base end of the bucket 133 is attached to a tip of the arm 132 via a pin.

The boom cylinder 134 is a hydraulic cylinder for actuating the boom 131. A base end of the boom cylinder 134 is attached to the rotating body 120. A tip end of the boom cylinder 134 is attached to the boom 131.
The arm cylinder 135 is a hydraulic cylinder for driving the arm 132. A base end of the arm cylinder 135 is attached to the boom 131. A tip end of the arm cylinder 135 is attached to the arm 132.
The bucket cylinder 136 is a hydraulic cylinder for driving the bucket 133. A base end of the bucket cylinder 136 is attached to the arm 132. A tip end of the bucket cylinder 136 is attached to a link mechanism that rotates the bucket 133.

The boom angle sensor 138 measures the stroke amount of the boom cylinder 134. The stroke amount of the boom cylinder 134 can be converted into the inclination angle of the boom 131 with respect to the revolving structure 120. Hereinafter, the inclination angle with respect to the revolving structure 120 will also be referred to as the absolute angle. In other words, the stroke amount of the boom cylinder 134 can be converted into the absolute angle of the boom 131.
The arm angle sensor 139 measures the stroke amount of the arm cylinder 135. The stroke amount of the arm cylinder 135 can be converted into an inclination angle of the arm 132 with respect to the boom 131. Hereinafter, the inclination angle of the arm 132 with respect to the boom 131 will also be referred to as the relative angle of the arm 132.
The bucket angle sensor 140 measures the stroke amount of the bucket cylinder 136. The stroke amount of the bucket cylinder 136 can be converted into the inclination angle of the bucket 133 with respect to the arm 132. Hereinafter, the inclination angle of the bucket 133 with respect to the arm 132 will also be referred to as the relative angle of the bucket 133.
In addition, the loading machine 100 according to other embodiments may be provided with an angle sensor that detects the inclination angle with respect to the ground plane or the inclination angle with respect to the rotating body 120, instead of the boom angle sensor 138, the arm angle sensor 139, and the bucket angle sensor 140.

The rotating body 120 is provided with a cab 121. Inside the cab 121, a cab 122 for an operator to sit on, an operation device 123 for operating the loading machine 100, and a detection device 124 for detecting the three-dimensional position of an object present in a detection direction are provided. The operation device 123 generates a lifting operation signal and a lowering operation signal for the boom 131, a pushing operation signal and a pulling operation signal for the arm 132, a dumping operation signal and an excavation operation signal for the bucket 133, and a left/right swing operation signal for the rotating body 120 in response to the operation of the operator, and outputs them to the control device 128. The operation device 123 also generates a loading instruction signal for causing the working machine 130 to start automatic loading control in response to the operation of the operator, and outputs it to the control device 128. The operation device 123 is composed of, for example, a lever, a switch, and a pedal. The loading instruction signal is generated by operating a switch for automatic control. For example, when the switch is turned ON, the loading instruction signal is output. The operation device 123 is disposed near the cab 122. The operating device 123 is located within an operable range of the operator when the operator sits in the driver's seat 122 .
Examples of the detection device 124 include a stereo camera, a laser scanner, and a UWB (Ultra Wide Band) distance measuring device. The detection device 124 is provided such that the detection direction faces, for example, forward of the cab 121 of the loading machine 100. The detection device 124 specifies the three-dimensional position of the target object in a coordinate system based on the position of the detection device 124.
The loading machine 100 according to the first embodiment operates according to the operation of an operator seated in the driver's seat 122, but other embodiments are not limited to this. For example, the loading machine 100 according to other embodiments may operate in response to an operation signal or a loading instruction signal transmitted by an operator remotely operating the loading machine 100 from outside the loading machine 100.

The loading machine 100 is equipped with a position and orientation calculator 125, an inclination measuring device 126, a hydraulic device 127, and a control device 128.

The position and orientation calculator 125 calculates the position of the revolving body 120 and the orientation in which the revolving body 120 faces. The position and orientation calculator 125 includes two receivers that receive positioning signals from artificial satellites that constitute the GNSS. The two receivers are installed at different positions on the revolving body 120. The position and orientation calculator 125 detects the position of a representative point of the revolving body 120 in the site coordinate system (the origin of the excavator coordinate system) based on the positioning signals received by the receivers.
The position and orientation calculator 125 uses the positioning signals received by the two receivers to calculate the orientation of the rotating body 120 as the relationship between the installation position of one receiver and the installation position of the other receiver. The orientation of the rotating body 120 is the front direction of the rotating body 120, and is equal to the horizontal component of the extension direction of a straight line extending from the boom 131 to the bucket 133 of the work machine 130.

The inclination measuring device 126 measures the acceleration and angular velocity of the rotating body 120, and detects the attitude of the rotating body 120 (e.g., roll angle and pitch angle) based on the measurement results. The inclination measuring device 126 is installed, for example, on the underside of the rotating body 120. The inclination measuring device 126 can be, for example, an inertial measurement unit (IMU).

The hydraulic device 127 includes a hydraulic oil tank, a hydraulic pump, and a flow control valve. The hydraulic pump is driven by the power of an engine (not shown) and supplies hydraulic oil to a traveling hydraulic motor (not shown) for traveling the traveling body 110, a swing hydraulic motor (not shown) for swinging the swing body 120, the boom cylinder 134, the arm cylinder 135, and the bucket cylinder 136 via the flow control valve. The flow control valve has a rod-shaped spool, and adjusts the flow rate of hydraulic oil supplied to the traveling hydraulic motor, the swing hydraulic motor, the boom cylinder 134, the arm cylinder 135, and the bucket cylinder 136 depending on the position of the spool. The spool is driven based on a control command received from the control device 128. In other words, the amount of hydraulic oil supplied to the traveling hydraulic motor, the swing hydraulic motor, the boom cylinder 134, the arm cylinder 135, and the bucket cylinder 136 is controlled by the control device 128. As described above, the boom cylinder 134, the arm cylinder 135, and the bucket cylinder 136 are driven by hydraulic oil supplied from the common hydraulic device 127. If the traveling hydraulic motor or the swing hydraulic motor is a swash plate type variable displacement motor, the control device 128 may adjust the rotation speed by the tilt angle of the swash plate.

The control device 128 receives an operation signal from the operation device 123. The control device 128 drives the work machine 130, the rotating body 120, or the running body 110 based on the received operation signal.

Configuration of the control device
FIG. 2 is a schematic block diagram showing the configuration of the control device according to the first embodiment.
The control device 128 is a computer including a processor 1100, a main memory 1200, a storage 1300, and an interface 1400. The storage 1300 stores a program. The processor 1100 reads the program from the storage 1300, loads it into the main memory 1200, and executes processing according to the program.

Examples of storage 1300 include HDD, SSD, magnetic disk, magneto-optical disk, CD-ROM, DVD-ROM, etc. Storage 1300 may be internal media directly connected to the common communication line of control device 128, or may be external media connected to control device 128 via interface 1400. Storage 1300 is a non-transitory tangible storage medium.

By executing the program, the processor 1100 is provided with a vehicle information acquisition unit 1101, a detection information acquisition unit 1102, an operation signal input unit 1103, a bucket position identification unit 1104, a loading position identification unit 1105, an avoidance position identification unit 1106, a movement processing unit 1107, an earth discharge start direction calculation unit 1108, an area determination unit 1109, and an operation signal output unit 1110.

The vehicle information acquisition unit 1101 acquires the rotation speed, position, and orientation of the rotating body 120, the inclination angles of the boom 131, arm 132, and bucket 133, and the attitude of the rotating body 120. Hereinafter, the information related to the loading machine 100 acquired by the vehicle information acquisition unit 1101 is referred to as vehicle information.

The detection information acquisition unit 1102 acquires three-dimensional position information from the detection device 124 and identifies the position and shape of the loading object 200 (e.g., a transport vehicle or a hopper).

The operation signal input unit 1103 receives input of an operation signal from the operation device 123. The operation signals include a raising operation signal and a lowering operation signal for the boom 131, a pushing operation signal and a pulling operation signal for the arm 132, a dumping operation signal and an excavation operation signal for the bucket 133, a rotation operation signal for the rotating body 120, a traveling operation signal for the traveling body 110, and a loading instruction signal for the loading machine 100. The dumping operation signal for the bucket 133 is an example of an earth removal operation signal.

Based on the vehicle information acquired by the vehicle information acquisition unit 1101, the bucket position identification unit 1104 identifies the position P of the tip of the arm 132 in the shovel coordinate system and the height Hb from the tip of the arm 132 to the lowest pass point of the bucket 133. The lowest pass point of the bucket 133 refers to the point at which the cutting edge is located when the distance between the cutting edge and the ground surface is the shortest during the dumping operation of the bucket 133. In other words, the height Hb from the tip of the arm 132 to the lowest pass point of the bucket 133 matches the length from the pin at the base end of the bucket 133 to the cutting edge.
Furthermore, the bucket position identifying unit 1104 identifies the position P of the tip of the arm 132 when the input of the loading command signal is received as the excavation completion position P10. Fig. 3 is a diagram showing an example of a path of the bucket according to the first embodiment.

Specifically, the bucket position identification unit 1104 identifies the position P of the tip of the arm 132 in the following procedure. The bucket position identification unit 1104 determines the position of the tip of the boom 131 based on the absolute angle of the boom 131 determined from the stroke amount of the boom cylinder 134 and the known length of the boom 131 (the distance from the pin at the base end to the pin at the tip). The bucket position identification unit 1104 determines the absolute angle of the arm 132 based on the absolute angle of the boom 131 and the relative angle of the arm 132 determined from the stroke amount of the arm cylinder 135. The bucket position identification unit 1104 determines the position P of the tip of the arm 132 based on the position of the tip of the boom 131, the absolute angle of the arm 132, and the known length of the arm 132 (the distance from the pin at the base end to the pin at the tip).

When a loading instruction signal is input to the operation signal input unit 1103, the loading position identification unit 1105 identifies the loading position P13 based on the position and shape of the loading target 200 identified by the detection information acquisition unit 1102. The loading position identification unit 1105 converts the loading point P21 indicated by the position information of the loading target 200 from the site coordinate system to the excavator coordinate system based on the position, orientation, and attitude of the revolving body 120 acquired by the vehicle information acquisition unit 1101. The loading position identification unit 1105 identifies the identified loading point P21 as the planar position of the loading position P13. In other words, when the tip of the arm 132 is located at the loading position P13, the tip of the arm 132 is located above the loading point P21. Examples of the loading point P21 include the center point of the vessel when the loading target 200 is a dump truck, and the center point of the opening when the loading target 200 is a hopper. The loading position identification unit 1105 identifies the height of the loading position P13 by adding the height Hb from the tip of the arm 132 to the lowest point of the bucket 133 identified by the bucket position identification unit 1104 and the height of the control margin of the bucket 133 to the height Ht of the loading target 200. Note that in other embodiments, the loading position identification unit 1105 may identify the loading position P13 without adding the height of the control margin. In other words, the loading position identification unit 1105 may identify the height of the loading position P13 by adding the height Hb to the height Ht. Note that the height Ht in the first embodiment is the height from the ground to the top surface of the vessel.

The avoidance position identification unit 1106 identifies an interference avoidance position P12, which is a point where the work machine 130 and the loading target 200 do not interfere with each other in a plan view from above, based on the loading position P13 identified by the loading position identification unit 1105, the position of the loading machine 100 acquired by the vehicle information acquisition unit 1101, and the position and shape of the loading target 200 identified by the detection information acquisition unit 1102. The interference avoidance position P12 is a position that has the same height as the loading position P13, is the same distance from the rotation center of the rotating body 120 as the distance from the rotation center to the loading position P13, and is below which the loading target 200 does not exist. For example, the avoidance position identification unit 1106 identifies a circle whose center is the center of rotation of the rotating body 120 and whose radius is the distance between the center of rotation and the loading position P13, and identifies, among the positions on the circle, the position closest to the loading position P13 and where the outline of the bucket 133 does not interfere with the loading target 200 in a plan view from above, as the interference avoidance position P12. The avoidance position identification unit 1106 can determine whether or not the loading target 200 and the bucket 133 interfere with each other based on the position and shape of the loading target 200 and the known shape of the bucket 133. Here, "the same height" and "equal distance" do not necessarily mean that the height or distance is completely the same, but rather allow for some error or margin.

When the operation signal input unit 1103 receives the input of the loading instruction signal, the movement processing unit 1107 generates a rotation operation signal for moving the bucket 133 to the loading position P13 based on the loading position P13 specified by the loading position specifying unit 1105 and the interference avoidance position P12 specified by the avoidance position specifying unit 1106. That is, the movement processing unit 1107 generates a rotation operation signal so that the bucket 133 reaches the loading position P13 from the excavation completion position P10 via the turning start position P11 and the interference avoidance position P12. The movement processing unit 1107 also generates a rotation operation signal for the bucket 133 so that the ground angle of the bucket 133 does not change even if the boom 131 and the arm 132 are driven. The operation signal generated by the movement processing unit 1107 is a signal that instructs driving at a drive amount related to the operation signal input to the operation signal input unit 1103 when the lever or pedal of the operating device 123 is operated with the maximum operation amount. The drive amount is, for example, the amount of hydraulic oil or the opening degree of the spool.
When the loading machine 100 is driven by remote control, the operation signal generated by the movement processing unit 1107 may be a signal instructing driving at a drive amount larger than the drive amount related to the maximum operation amount. This is because, while the loading machine 100 related to manned operation has a maximum operation amount of the operation device 123 limited for the riding comfort of the operator, the loading machine 100 related to remote operation is not limited by the riding comfort of the operator.

The soil discharge start orientation calculation unit 1108 calculates the soil discharge start orientation D0 based on the position of the loading target 200, the rotation speed of the revolving body 120, and the soil discharge delay time from the time when a dump operation instruction is output for the bucket 133 to the time when the soil discharge starts. The soil discharge start orientation D0 is an orientation in which soil is discharged to the loading target 200 without spilling if a dump operation instruction is output when the revolving body 120 faces that orientation during the rotation of the revolving body 120. The soil discharge delay time of the bucket 133 is known for each model of the loading machine 100.
For example, the soil discharge start orientation calculation unit 1108 calculates the soil discharge start orientation D0 in the following procedure. The soil discharge start orientation calculation unit 1108 calculates the soil discharge arrival time from the bucket 133 to the loading target 200 based on the distance from the lowest point of the bucket 133 to the loading target 200. The soil discharge start orientation calculation unit 1108 calculates the soil discharge rotation angle θ by multiplying the rotation speed by the sum of the soil discharge delay time and the soil discharge arrival time. The soil discharge start orientation calculation unit 1108 calculates, as the soil discharge start orientation D0, an orientation rotated by the soil discharge rotation angle θ toward the front side of the rotation direction from the orientation D1 in which the revolving body 120 faces when the entire width of the blade tip of the bucket 133 overlaps with the loading target 200 in a plan view from above.

The area determination unit 1109 determines whether the orientation of the rotating body 120 is in the first area R1 in which no soil discharge operation is performed, or in the second area R2 in which soil discharge operation is performed. The first area R1 is the area from the orientation (starting point orientation) in which the rotating body 120 is facing when the input of the loading instruction signal is received to the soil discharge start orientation D0. The second area R2 is the area from the soil discharge start orientation D0 to the orientation (end point orientation) in which the rotating body 120 is facing when the work machine 130 is located at the loading position P13. Note that the soil discharge start orientation D0 is always located on the near side in the rotation direction from the end point orientation.

The operation signal output unit 1110 outputs an operation signal input to the operation signal input unit 1103 or an operation signal generated by the movement processing unit 1107. Specifically, when automatic loading control is in progress, the operation signal output unit 1110 outputs an operation signal related to automatic control generated by the movement processing unit 1107, and when automatic loading control is not in progress, outputs an operation signal related to manual operation by the operator input to the operation signal input unit 1103.

"motion"
When the operator of the loading machine 100 determines that the loading machine 100 and the loading target 200 are in a positional relationship that allows loading processing, he or she turns on a switch for automatic control of the operation device 123. As a result, the operation device 123 generates and outputs a loading instruction signal.

Figures 4 and 5 are flowcharts showing the automatic loading control method according to the first embodiment. When the control device 128 receives a loading instruction signal input from the operator, it executes the automatic loading control shown in Figures 4 and 5.

The vehicle information acquisition unit 1101 acquires the position and orientation of the rotating body 120, the tilt angles of the boom 131, arm 132, and bucket 133, and the attitude of the rotating body 120 (step S1). The vehicle information acquisition unit 1101 identifies the position of the center of rotation of the rotating body 120 based on the acquired position and orientation of the rotating body 120 (step S2). The detection information acquisition unit 1102 also acquires three-dimensional position information of the loading target 200 from the detection device 124, and identifies the position and shape of the loading target 200 from the three-dimensional position information (step S3).

The bucket position identification unit 1104 identifies the position P of the tip of the arm 132 when the loading command signal is input and the height Hb from the tip of the arm 132 to the lowest passing point of the bucket 133 based on the vehicle information acquired by the vehicle information acquisition unit 1101 (step S4). The bucket position identification unit 1104 identifies the position P as the excavation completion position P10.

The loading position identification unit 1105 converts the position information of the loading target 200 acquired by the detection information acquisition unit 1102 from the site coordinate system to the excavator coordinate system based on the position, orientation, and posture of the rotating body 120 acquired in step S1. The loading position identification unit 1105 identifies the planar position of the loading position P13 based on the position and shape of the loading target 200 identified by the detection information acquisition unit 1102 (step S5). At this time, the loading position identification unit 1105 identifies the height of the loading position P13 by adding the height Hb from the tip of the arm 132 to the lowest point of the bucket 133 identified in step S4 and the height of the control margin of the bucket 133 to the height Ht of the loading target 200 (step S6).

The avoidance position identification unit 1106 identifies the planar distance from the position of the center of rotation of the rotating body 120 identified in step S2 to the planar position of the loading position P13 (step S7). The avoidance position identification unit 1106 identifies as the interference avoidance position P12 the position that is the identified planar distance away from the center of rotation, where the outline of the bucket 133 does not interfere with the loading target 200 in a planar view, and is closest to the loading position P13 (step S8).

The movement processing unit 1107 determines whether the position P of the tip of the arm 132 has reached the loading position P13 (step S9). If the position P of the tip of the arm 132 has not reached the loading position P13 (step S9: NO), the movement processing unit 1107 determines whether the position P of the tip of the arm 132 is in the vicinity of the interference avoidance position P12 (step S10). For example, the movement processing unit 1107 determines whether the difference between the height of the tip of the arm 132 and the height of the interference avoidance position P12 is less than a predetermined threshold value, or whether the difference between the planar distance from the center of rotation of the rotating body 120 to the tip of the arm 132 and the planar distance from the center of rotation to the interference avoidance position P12 is less than a predetermined threshold value (step S10). If the position P of the tip of the arm 132 is not in the vicinity of the interference avoidance position P12 (step S10: NO), the movement processing unit 1107 generates an operation signal to raise the boom 131 and the arm 132 to the height of the interference avoidance position P12 (step S11). At this time, the movement processing unit 1107 generates an operation signal based on the position and speed of the boom 131 and arm 132.

The movement processing unit 1107 also calculates the sum of the angular velocities of the boom 131 and the arm 132 based on the generated operation signals of the boom 131 and the arm 132, and generates an operation signal to rotate the bucket 133 at a speed equal to the sum of the angular velocities (step S12). This allows the movement processing unit 1107 to generate an operation signal that maintains the ground angle of the bucket 133. Note that in other embodiments, the movement processing unit 1107 may generate an operation signal to rotate the bucket 133 so that the ground angle of the bucket 133 calculated from the detection values of the boom angle sensor 138, the arm angle sensor 139, and the bucket angle sensor 140 becomes equal to the ground angle at the start of automatic control.

When the position P of the tip of the arm 132 is near the interference avoidance position P12 (step S10: YES), the movement processing unit 1107 does not generate operation signals for the boom 131, the arm 132, and the bucket 133. In other words, when the position P of the tip of the arm 132 is near the interference avoidance position P12, the movement processing unit 1107 prohibits the output of an operation signal for the work machine 130 to move the work machine 130 to the loading point.

The movement processing unit 1107 determines whether or not the rotation speed of the rotating body 120 is less than a predetermined speed based on the vehicle information acquired by the vehicle information acquisition unit 1101 (step S13). That is, the movement processing unit 1107 determines whether or not the rotating body 120 is rotating.
If the rotation speed of the rotating body 120 is less than the predetermined speed (step S13: YES), the movement processing unit 1107 specifies a rise time, which is the time it takes for the height of the bucket 133 to reach the height of the interference avoidance position P12 from the height of the excavation completion position P10 (step S14). The movement processing unit 1107 determines whether or not the tip of the arm 132 will pass through the interference avoidance position P12 or a point higher than the interference avoidance position P12 when a rotation operation signal is output from the current time based on the rise time of the bucket 133 (step S15). If the tip of the arm 132 will pass through the interference avoidance position P12 or a point higher than the interference avoidance position P12 when a rotation operation signal is output from the current time (step S15: YES), the movement processing unit 1107 generates a rotation operation signal (step S16).
If the tip of the arm 132 passes a point lower than the interference avoidance position P12 when a rotation operation signal is output from the current time (step S15: NO), the movement processing unit 1107 does not generate a rotation operation signal. In other words, if the tip of the arm 132 passes a point lower than the interference avoidance position P12, the movement processing unit 1107 prohibits the output of the rotation operation signal.

If the rotation speed of the revolving body 120 is equal to or higher than a predetermined speed (step S13: NO), the movement processing unit 1107 judges whether or not the tip of the arm 132 will reach the loading position P13 when the output of the revolving operation signal is stopped from the current time (step S17). After the output of the revolving operation signal is stopped, the revolving body 120 continues to rotate by inertia while decelerating, and then stops. If the tip of the arm 132 reaches the loading position P13 when the output of the revolving operation signal is stopped from the current time (step S17: YES), the movement processing unit 1107 does not generate a revolving operation signal. In other words, if the tip of the arm 132 reaches the loading position P13 when the output of the revolving operation signal is stopped from the current time, the movement processing unit 1107 prohibits the output of the revolving operation signal. As a result, the revolving body 120 starts to decelerate.
On the other hand, if the output of the rotation operation signal is stopped from the current time, and the tip of the arm 132 is to stop short of the loading position P13 (step S17: NO), the movement processing unit 1107 generates a rotation operation signal (step S18).

When at least one of the rotation operation signals for the boom 131, arm 132, and bucket 133, and the rotation operation signal for the rotating body 120 is generated in the processing from step S9 to step S18, the operation signal output unit 1110 outputs the generated operation signal to the hydraulic device 127 (step S19).

Next, the discharge start direction calculation unit 1108 calculates the discharge start direction D0 based on the position of the loading target 200, the rotation speed of the revolving body 120, and the discharge delay time (step S20). The area determination unit 1109 determines whether the direction in which the revolving body 120 faces is included in the second area R2 from the discharge start direction D0 to the end point direction (step S21). If the direction in which the revolving body 120 faces is included in the first area R1 (step S21: NO), the operation signal output unit 1110 does not output the dump operation signal of the bucket 133 to the hydraulic device 127. On the other hand, if the direction in which the revolving body 120 faces is included in the second area R2 (step S21: YES), the operation signal output unit 1110 outputs the dump operation signal of the bucket 133 to the hydraulic device 127 (step S22).

When the orientation in which the revolving unit 120 faces is included in the second region R2, the height of the tip of the arm 132 is equal to or higher than the interference avoidance position P12. This is because, in steps S15-S16, the movement processing unit 1107 generates a revolving operation signal so that the height of the tip of the arm 132 is equal to or higher than the interference avoidance position P12 when the tip of the arm 132 is located at the interference avoidance position P12 in a plan view from above. The orientation in which the revolving unit 120 faces when the tip of the arm 132 is located at the interference avoidance position P12 in a plan view from above is located on the near side in the revolving direction from the soil discharge start orientation D0.
Furthermore, even if the direction in which the revolving unit 120 faces is included in the first region R1, the height of the tip of the arm 132 is not necessarily a height below the interference avoidance position. For example, if the time required to raise the height of the arm 132 to a height equal to or higher than the interference avoidance position P12 is shorter than the time required to rotate the revolving unit 120 until the tip of the arm 132 is positioned at the interference avoidance position P12 in a plan view from above, the direction in which the revolving unit 120 faces when the height of the tip of the arm 132 has risen to a height equal to or higher than the interference avoidance position P12 may be included in the first region R1.

Then, the vehicle information acquisition unit 1101 acquires vehicle information (step S23). This allows the vehicle information acquisition unit 1101 to acquire vehicle information after operation by the output operation signal. The control device 128 returns the process to step S9 and repeats the generation of the operation signal.

On the other hand, if in step S9 the position P of the tip of the arm 132 reaches the loading position P13 (step S9: YES), the control device 128 ends the automatic loading control.

Now, the operation of the loading machine 100 during automatic loading control will be described with reference to FIG. 3. When automatic loading control is started, the boom 131 and the arm 132 rise from the excavation completion position P10 toward the rotation start position P11. At this time, the bucket 133 is driven so as to maintain the ground angle at the time of the end of excavation.

When the tip of the arm 132 reaches the rotation start position P11, the control device 128 controls the rotating body 120 to start rotating toward the loading position P13. At this time, the tip of the arm 132 has not yet reached the height of the interference avoidance position P12, so the boom 131 and arm 132 continue to rise. As the tip of the arm 132 moves from the rotation start position P11 to the interference avoidance position P12, the boom 131, arm 132, and bucket 133 decelerate so that the height of the tip of the arm 132 becomes equal to that of the interference avoidance position P12.

When the tip of the arm 132 reaches the interference avoidance position P12, the drive of the boom 131 and arm 132 stops. Meanwhile, the rotating body 120 continues to rotate. In other words, between the interference avoidance position P12 and the loading position P13, the tip of the arm 132 moves only by the rotation of the rotating body 120, not by the drive of the boom 131 and arm 132. As the tip of the arm 132 moves from the rotation start position P11 to the loading position P13, the rotating body 120 decelerates so that the position P of the tip of the arm 132 becomes equal to the loading position P13.

As the tip of the arm 132 moves from the rotation start position P11 to the loading position P13, the rotating body 120 faces the soil discharge start direction D0. At this time, the control device 128 starts outputting a dump operation signal to the bucket 133. The rotating body 120 continues to rotate, and when the soil discharge delay time has elapsed from the time the dump operation signal was output, the bucket 133 begins to rotate in the dump direction, and soil begins to be discharged from the bucket 133. When soil begins to be discharged, the direction in which the rotating body 120 faces is forward in the rotation direction of the direction D1 where the width of the blade of the bucket 133 overlaps with the loading target 200. The soil discharged from the bucket reaches the height of the loading target 200 after the soil arrival time. Since the loading machine 100 unloads soil while rotating, the soil discharged from the bucket 133 draws a parabola with a horizontal velocity component in the tangential direction due to inertia according to the rotation speed, and falls from the unloading start point toward the rear of the rotation direction. In other words, the unloading start direction D0 is a direction in which the bucket 133 is not directly above the loading target 200, but if the output of a dump operation signal is started when the rotating body 120 faces the unloading start direction D0, the soil will fit within the loading target 200 due to the unloading delay time and the horizontal velocity component of the soil. Therefore, the control device 128 can load the soil into the loading target 200 without spilling it by starting to output a dump operation signal to the bucket 133 when the rotating body 120 faces the unloading start direction D0.

When the tip of the arm 132 reaches the loading position P13 and the dump operation of the bucket 133 is completed, the drive of the work machine 130 and the rotating body 120 stops.

By using the automatic loading control described above, the loading machine 100 can load the soil scooped up by the bucket 133 onto the loading target 200. The operator repeatedly performs excavation using the work machine 130 and automatic loading control by inputting a loading command signal, to the extent that the load capacity of the loading target 200 does not exceed the maximum load capacity.

<Action and Effects>
In this way, the control device 128 of the loading machine 100 according to the first embodiment outputs a dump operation signal for the bucket 133 to the hydraulic device 127 when the revolving body 120 faces the soil discharge start direction D0 on the front side of the revolving direction from the end point direction during automatic loading control. This allows the control device 128 to start soil discharge before the bucket 133 reaches the loading position P13, thereby shortening the cycle time of the loading process. Note that the control device 128 according to the first embodiment determines whether or not to output the dump operation signal based on whether the orientation of the revolving body is included in the first region or the second region, but is not limited to this. For example, the control device 128 according to other embodiments may determine whether or not to output the dump operation signal based on whether or not the orientation of the revolving body has exceeded the soil discharge start direction D0.

In addition, the discharge start orientation D0 in the first embodiment is an orientation on the near side of the rotation direction than the orientation D1 to which the rotating body 120 faces when the width of the blade tip of the bucket 133 and the loading target 200 overlap in a plan view from above. This allows the control device 128 to advance the timing at which the dump operation signal starts to be output, thereby shortening the cycle time. On the other hand, other embodiments are not limited to this, and the control device 128 may start outputting the dump operation signal when the width of the blade tip of the bucket 133 and the loading target 200 overlap in a plan view from above. In this case, the control device 128 can reliably prevent soil from spilling from the loading target 200.

The control device 128 according to the first embodiment also calculates the soil discharge start direction D0 based on the position of the loading target 200 and the rotation speed of the rotating body 120. This allows the control device 128 to appropriately determine the timing to start outputting the dump operation signal according to the rotation speed of the rotating body 120. Note that other embodiments are not limited to this, and the control device 128 may start outputting the dump operation signal based on a predetermined soil discharge start direction D0.

Although one embodiment has been described in detail above with reference to the drawings, the specific configuration is not limited to the above, and various design modifications and the like are possible.
For example, in the first embodiment, the discharge start orientation D0 is a position calculated based on the position of the loading target 200, the rotation speed of the rotating body 120, the discharge delay time, and the soil arrival time, but is not limited to this. For example, in other embodiments, the discharge start orientation D0 may be calculated without taking into account the discharge delay time or the soil arrival time. In other embodiments, the discharge start orientation D0 may be an orientation closest to the starting point orientation among the orientations in which the tip of the arm 132 interferes with the loading target 200 in a plan view from above. In other embodiments, the discharge start orientation D0 may be set to any orientation on the starting point orientation side among the orientations in which the tip of the arm 132 interferes with the loading target 200 in a plan view from above. In other embodiments, the discharge start orientation D0 may be set to any orientation on the ending point orientation side among the orientations in which the tip of the arm 132 does not interfere with the loading target 200 in a plan view from above. In another embodiment, the soil discharge start orientation D0 may be set to the orientation in which the rotating body faces when the tip of the arm 132 is located at the interference avoidance position P12.

The loading machine 100 according to the first embodiment is equipped with a bucket 133, but is not limited to this. For example, the loading machine 100 according to other embodiments may be equipped with a clam bucket that includes a back hoe and a clam shell that can be opened and closed. In this case, the soil discharge operation signal is an operation signal that rotates the clam shell.

The loading machine 100 according to the first embodiment is a manned vehicle operated by an operator, but is not limited to this. For example, the loading machine 100 according to another embodiment may be a remotely operated vehicle that is operated by an operation signal acquired by communication from a remote control device operated by an operator in a remote office while watching a monitor screen. In this case, some of the functions of the control device 128 may be provided in the remote control device. The loading machine 100 according to the first embodiment performs the control shown in Figures 4 and 5 in the automatic loading control, but is not limited to this. For example, the loading machine 100 according to another embodiment may perform the control shown in Figures 4 and 5 in the automatic excavation and loading control that automatically performs excavation and loading operations repeatedly.

100...loading machine 110...traveling body 120...rotating body 130...working machine 131...boom 132...arm 133...bucket 134...boom cylinder 135...arm cylinder 136...bucket cylinder 128...control device 1101...vehicle information acquisition unit 1102...detection information acquisition unit 1103...operation signal input unit 1104...bucket position identification unit 1105...loading position identification unit 1106...avoidance position identification unit 1107...movement processing unit 1108...earth discharge start direction calculation unit 1109...area determination unit 1110...operation signal output unit 200...loading target P10...digging completion position P11...turn start position P12...interference avoidance position P13...loading position R1...first area R2...second area D0...earth discharge start direction θ...earth discharge turn angle

Claims (10)

A control device for a loading machine including a rotating body that rotates around a rotation center and a work machine having a bucket and attached to the rotating body,
a control device for a loading machine, the control device including: an operation signal output unit that outputs an earth-discharging operation signal for discharging earth into the bucket before the bucket reaches above the loading target in an automatic loading control for moving the bucket above the loading target. The operation signal output unit outputs the soil discharge operation signal before the bucket reaches above the vessel or the opening of the hopper in the automatic loading control for moving the bucket above the vessel of the dump truck that is the loading target or the opening of the hopper that is the loading target.
The control device for a loading machine according to claim 1. The control device for a loading machine according to claim 1, wherein the operation signal output unit outputs the earth-discharging operation signal during a swing. The operation signal output unit outputs the soil discharge operation signal for causing the bucket to discharge soil in a direction forward in a rotation direction from a direction in which the bucket faces when the bucket reaches above the loading target.
The control device for a loading machine according to claim 1 or 2. A soil discharge start direction calculation unit is provided which calculates a direction in which the soil is discharged into the bucket based on the position of the loading target and the rotation speed of the rotating body.
The control device for a loading machine according to claim 4 . The direction in which the earth removal operation signal is output is a predetermined direction.
The control device for a loading machine according to claim 4 or 5 . A region determining unit is provided for determining whether the direction of the bucket is in a first region in which the earth-discharging operation is not performed or in a second region in which the earth-discharging operation is performed.
The control device for a loading machine according to any one of claims 4 to 6 . When the area determination unit determines that the orientation of the bucket is included in the second area, the operation signal output unit outputs the earth unloading operation signal for unloading the bucket.
The control device for a loading machine according to claim 7 . A control method for a loading machine including a rotating body that rotates about a rotation center and a work machine having a bucket and attached to the rotating body, comprising:
a step of outputting an earth-discharging operation signal for discharging earth into the bucket before the bucket reaches above the loading target in an automatic loading control for moving the bucket above a loading target. A remote control system for a loading machine including a rotating body that rotates about a rotation center and a work machine having a bucket and attached to the rotating body,
a remote control system for a loading machine, the system including: an operation signal output unit that outputs an earth-discharging operation signal for discharging earth into the bucket before the bucket reaches above the loading target in an automatic loading control for moving the bucket above the loading target.

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